Brake



Feb. 2 1926.

. B. E. FERNOW, JR

BRAKE Filed July 2, 1921 Patented Feb. 2, 192$.

UNtTED STATES PATENT OFFIQE.

BERNHARD FERNOW, JR., 011' MILNAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER?HAMMER MFG. 00., OF MILWAUKEE, WISCONSIN, .A GOREOBATION OF WISCONSIN.'

BRAKE.

Application filed July 2, 1921. Serial No. 482,070.

To a 10/20/77, it may cul'zccrn:

Be it known that I, BERNI-IARI) E. FERNOW, diu, a citizen of the UnitedStates, residing at li'iilwaukee. in the county of Milwaukee and Stateoi Wisconsin, have invented new and useful Improvements in Brakes, of

which the following is a full, clear, concise, and exact description,reference being had to the accompanying drawing, forming a m 'r-art 01".this specification.

This invention relates to improvements 1n brakes and more particularlyto electron'iae'netic brakes oi the drum type.

Such brakes are commonly provided with 5 op- 'iosed brake shoes having aspring pres sure device associated therewith for setting the same and anelectro-magnet for effecting release thereof. The field member of theclectroanagnet is usually fixed to a stationary support while thearmature member hereof is usually connected to the brake slices throughthe medium of a toggle. In practice it has been found exceedinglydifficult to maintain the parts of the brake in 4 proper adjustmentsince a slight oft centering ot the drum with respect to the shoesprevents equalization of the setting pres sure on the shoes and alsoprevents sealing of the armature with the field member upon release ofthe brake.

The present invention has among its objects to provide anelectromagnetic brake of the drum type having its parts arranged so thatequalization ot the setting pressure on the shoes and sealing of thearmature .men'iber with the field member are not dependent upon exactcentering of the drum with respect to the shoes.

Another object is to provide a rugged, compact and eflicient brake ofthe aforesaid chu 'acter having its parts arranged to mal'tlltl-llyreduce the overhead space required by the brake.

Smother object is to simplify and reduce the number of parts in theoperating mechanism oi? the brake.

Various other objects and advantages of the invention will hereinafterappear.

The accompanying drawing illustrates a brake embodying the invention inone form and the same will now be described, it being understood thatthe brake illustrated 1s susceptible of various modifications withoutdeparting'trom thescope of the appended claim. i

c In the drawing,

} Fig. 1 is a side elevational view of the brake;

Fig. 2 is an end view thereof; and,

r Fig. 3 is awsectional view on line 3-8 of Referring to the drawing thesame illustrates a drum 1 to be secured to the motor or other device tobe braked, opposed brake shoes 2 and 3 to :trictionally engage said drumand levers 4 and 5 supporting said shoes respectively. Each of saidlevers comprises a pair of parallel side arms arranged on opposite sidesof a base 6, the former lever having its lower end pivotal'ly secured tosaid base by a pin 7 and the latter having its lower end pivotallysecured thereto by a pin 8. Brakeshoes 2 and 3 are arranged between thearms of their respective levers and are pivotally secured. thereto bypins 9 and 10 respectively and-each of said levers is provided with aconnecting web 11 carrying an adjustable stop 12 for the lower end ofits respective shoe.

Shoes 2 and 3 are normally held against drum 1 under action of a spring13, said spring being operatively connected to levers 4 and 5 throughthe medium of rods 14 and 15 and yoke member 16 between said rods. Rod15 has its left end slidably mounted within a block 17 pivotally securedat 18 to the upper end of lever 4 and said rod is adjustable within saidblock by nuts 19 arranged on opposite sides of the latter. Rod 14 isslidable within an opening in a connecting web 20 located adjacent theupper end of lever 5 and spring 13 is held under compression betweenwashers 21 and 22, the former washer being slidable on rod 14, said weband the latter being adjustable on rod 14 by nuts 23.

The brake releasing means includes a field member 24 provided with awinding 25 and an armature member 26 to be attracted by said Winding.Field member 24 is made up of U-shaped laininations secured to a bracket27, said bracket having a projecting arm 28 secured by pins 29 to lugs30 on the arms of lever 5. Armature member 26 is up of laminationssecured to a lever 31. Lever 31 extends upwardly through yoke member 16and is pivotally securedto said: yoke member by a pin 32 as shown inFig. 3, and is also pivotally secured to lever 5 immediately above saidyoke member by a pin 33.

From the foregoing it is: apparent that spring 13 serves to normallybias arms 4' and; 5 towards each other to set brake shoes 2 and 3against drum 1 and to normally hold armature member 26 in the positionindicated; by dotted lines. Upon energization of winding 25, armaturemember 26 is attracted to the position shown in full lines and duringsuch movement lever 31 acts through the medium of yoke member 16 and rod1 5 to spread levers 4 and 5 apart against the action of spring 13 forrelease of' the brake;

It should be noted that with the parts of the brake arranged" as abovedescribed 01f centering of the drum 1 with respect to the brake levers4t and 5 does not prevent seal-- ing of armature 26' with the pole facesof field member- 24, and that the range of move-r ment of thearmaturecan be readily varied by adjustment of rod 15 with respect toblock 17. Furthermore it should be noted that even tho-ugh drum 1 is outof centered relation with respect to levers 4 and 5, said levers willadjust themselves to suit the position of the drum and will exert equalsetting pressures on shoes: 2' and 3' under the action of spring 13.

To equalize the releasing movement of;

arms l and 5 webs 11 thereof are provided with adjustable stops 34arranged to cooperate with fixed stops 35' on opposite ends of base 6.Ordinarily only one of the stops 3 1 is employed, the left hand stopbeing used when the brake is mounted in a position wherein lever 5tends: to move by gravity towards the drum and the right hand stopbeing. used when said lever tends to move by gravity in an oppositedirection.

' What I claim as new and desire to secure by Letters Patent is:

The combination with a brake drum, of a stationary supporting base toone side thereof, a pair, of substantially parallel supporting armspivoted to said base and arranged onopposite sides of said drum, brakeshoes pivotal'ly secured to said arms, a rigid link extending betweensaid arms, said link being pivotally and adjustably connected at one endthereof'to the, free end of one of said supportin arms, a brakeoperating member pivotal y connected to said link and having one endthereof pivotally connected to the free end of the other of saidsupporting arms, an armature port-ion fixed to the free end of saidoperating member, an elec tromagnet including a field member fixed to.

said latter supporting arm and spring means associated with said linkfor effecting setting of said brake shoes.

In witness whereof, I have hereunto subscribed my name.

BERNHARD E. FERNOV, JR.

